How to ask magit to use external diff and merge tools?

Question

I have set the git variables [merge] and [diff] to the appropriate values like this:

[merge]
    keepBackup = false;
    tool = p4merge
[mergetool]
    prompt = false
[mergetool "p4merge"]
    cmd = p4merge "$BASE" "$LOCAL" "$REMOTE" "$MERGED"
    keepTemporaries = false
    trustExitCode = false
    keepBackup = false
[diff]
    tool = p4merge
[difftool]
    prompt = false
[difftool "p4merge"]
    cmd = p4merge "$LOCAL" "$REMOTE"
    keepTemporaries = false
    trustExitCode = false
    keepBackup = false

and this works from the command line. I am not sure how to open external diff and merge tools from within magit.

I found this tool https://github.com/Perlmint/magit-exttool , but it doesn't work.

Answer 1

Magit does not support invoking external diff tools and it will be a very long time until I get around to implementing such support because I am focused on improving the internal tools instead so that there are fewer reasons to want to use an external tool.